What “calls to action” deliver the best results, and how are those results measured?
In my experience, the best calls to action for digital signage all involve the use of the mobile phone as the conduit. Digital signage is experienced when a person is out of their home and going about their day. Calls to action that extend the commercial message from the digital screen to the mobile phone, so that the consumer then carries that message with them after engaging with the screen, can be very powerful. The mobile phone has the ability to then help direct the consumer from the screen to a retail location. In addition to serving as a wayfinding tool, the mobile phone can also store a digital coupon to help further push the consumer to the desired retail location, or even to a website for redemption in an online purchase. There are all kinds of ways to use the mobile phone as a call to action including but not limited to SMS, NFC, Bluetooth and/or app downloads. All of these technologies have pluses and minuses, but all of them can be used to extend the message from the digital display to the mobile phone in order to elicit a specific action from the consumer.
With regard to how best to measure the effectiveness of the strategy, the first and most obvious is sales. How many people engaged with the screen, took information from the screen (via SMS, etc.) and then used that information to make a purchase. Other measurements can be used as well depending the objectives of the campaign. Maybe the call to action was to drive web traffic. Web analytic tools can easily show web traffic in relation to where the screens displayed the advertising message. Unique URL codes can also be used in different geographies and across different platforms to track which calls to action are having the best results. Ultimately, the best ways to measure the effectiveness of a call to action depends a great deal on what that call to action was and what it was driving to.